Feature request: ACME plugin: Add an automation to upload certificates to Proxmox Mail Gateway

[Grandma-Betty]

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• [x] I have read the contributing guide lines at https://github.com/opnsense/plugins/blob/master/CONTRIBUTING.md
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Is your feature request related to a problem? Please describe. Currently there is an existing automation option to upload certificates to Proxmox PVE, but no option to upload certificates to Proxmox Mail Gateway.

Describe the solution you'd like It would be nice to have the possibility to upload certificates to Proxmox Mail Gateway too. Should not be that much of a deal I guess as the web interface UI for uploading certificates manually is almost the same on Proxmox PVE and Proxmox Mail Gateway.

Describe alternatives you've considered None.

Additional context None.